We have two challenges deploying our application for Ubuntu/Debian:
1. Offline installation
Many (let’s say 50%) of our users will need to install offline. They will have zero internet connectivity. Thus, we need to include all possible dependencies (run time / third-party libraries, etc.) on an installation CD/DVD. It looks like perhaps APT-on-CD might be a solution here, but the documentation I read wasn’t exactly clear.
2. Not-yet-supported versions of packages
Some dependencies are not yet supported by the “official” Ubuntu repositories. For example, version 4.2 of a particular library is provided in the Software Center, but my application requires version 4.4–which is a stable release, just not in the official repository packages. (The stable distribution of Debian is even further behind, still in version 3.)
- Should I then initially create my own .deb package for these, or just install the libraries in somewhere like
/usr/lib/myapp? - If I create my own .deb, should I give it the same (likely) name as the official package? That is, I would anticipate many (if not all) of these packages to be officially provided at some time in the future. Thus, ideally the installation procedure (in an online situation) would look first to the official repositories for the library, but be able to fall back to the CD/DVD if necessary. Is this possible, or do I just name by package something totally different and let it permanently live side-by-side?
What are the best practices for handling these installation challenges?
1) if you have packages on a media of some sort, there should be no need to use apt, just simple dpkg -i /where/your/media/is/mounted/*.deb should be enough to install things ?
2) Alternative of shipping packages that are not yet supported by your distro but keeping your clients distro compatible with what ever software they have is to repackage those dependencies. Change the name of the package by adding a prefix to it and change the installation directory something like /opt/prefix/ instead of /usr
The compile your application with -rpath flag pointing to the location where your required libraries are provided (afaik debian rules disallow rpath usage thou) or make your application start only from a shellscript that sets a proper LD_LIBRARY_PATH before it starts your real application.